70 DISSECTION OF THE DOG 



The duodenum runs along the lateral border of the right kidney, and the 

 spleen comes into contact with part of the corresponding border of the left 

 organ. Cranially the right kidney fits into a deep fossa formed by the right 

 lateral lobe and the caudate process of the liver ; the left kidney is embraced 

 by the dorsal end of the spleen. 



In the male the caudal end of each kidney is related to the small intes- 

 tine. In the female this end is connected with the ovary by means of the 

 mesovarium. 



Hilus renalis. — The hilus of the kidney affords a means of entrance and 

 exit for the various blood-vessels, nerves, and lymphatics, and the ureter. Of 

 the three main structures connected therewith, the renal artery is the most 

 dorsal, the renal vein the most ventral, and the ureter between the two. The 

 lymphatics and nerves are mainly dorsal to the vein. 



Interior of the kidney. — The surface of the kidney is covered by a strong 

 fibrous capsule, which can be readily stripped off except where it is continuous 

 with the sheaths of the several structures entering the organ at the hilus. 



A section of the organ should be made by entering the knife at the lateral 

 border and carrying it to the hilus. When this has been done, the two portions 

 of kidney substance, cortex and medulla, are revealed. The cortical substance 

 presents a granular appearance ; whereas the medullary substance is striated. 

 In the boundary zone between the two, the cut ends of numerous large vessels 

 will be noted. 



The innermost part of the medullary substance is paler in colour than the rest 

 and forms a curved ridge running longitudinally to the long axis of the kidney 

 and projecting into a cavity known as the pelvis (pelvis renalis). The cavity of 

 the pelvis is elongated in conformity with the general form of the kidney itself, 

 and has a crescentic outline, each horn of the crescent being abruptly recurved 

 to produce a terminal recess (recessus terminalis). In the concavity of the 

 crescent is a funnel-shaped portion of the pelvis leading into the ureter. 



Ureter. — Immediately upon its exit from the hilus of the kidney, the 

 ureter curves towards the pelvis and runs along the psoas muscles under the 

 peritoneum. Crossing the ductus deferens in the male close to the pelvic inlet, 

 or piercing the broad ligament of the uterus in the female, the ureter ends by 

 obliquely piercing the wall of the neck of the bladder. 



Glandule suprarenales.— The adrenal or suprarenal glands are two 

 irregularly triangular objects found in the neighbourhood of the hilus of the 

 kidney. The ventral surface of each is crossed by a deep groove in which 

 the phrenico-abdominal vein is lodged. On section, the organs reveal a 

 pale cortical substance, and a darker, more vascular, and somewhat softer, 

 medullary substance. 



Dissection. — With great care remove the fat which lies dorsal to the kidneys 

 and about the aorta as it passes through the diaphragm. The greater 



